Finger fractures are the most common types of fractures seen in primary care settings. Many of these fractures are sport or work related, but they may also occur in common activities of daily living such as housework, cleaning, and dressing. Finger fractures may be caused by blunt trauma, hyperextension, hyperflexion, or twisting forces. Distal phalanx fractures are the most common followed in frequency by proximal phalanx fractures and fractures of the middle phalanx. Most phalangeal fractures heal well without complication. Angulated or malrotation deformities can occur as a result of the numerous tendon attachments and muscle forces acting across fracture fragments. Knowledge of the typical deforming forces and evaluation of fracture stability are essential in the management of finger fractures.
See Appendix for stepwise instructions for gutter and thumb spica splints used in the treatment of finger fractures.
Go to Expert Consult for the electronic version of a patient instruction sheet named “Broken Hand or Wrist,” which covers the steps of care from pain relief to rehabilitation exercises. This can be copied to hand out to patients to assist them during the treatment period.
Distal Phalanx Fractures
The extensor tendon splits at the midpoint of the proximal phalanx, forming the central slip that inserts on the middle phalanx and the lateral bands that reunite to insert at the dorsum of the base of the distal phalanx. The flexor digitorum profundus (FDP) inserts at the volar base of the distal phalanx. The FDP pulls the distal interphalangeal (DIP) joint into flexion when the extensor tendon is avulsed. Fibrous septa extend from the volar aspect of the distal phalanx to the skin. These fibrous septa support the distal phalanx, and thus most fractures in this location are stable.
Mechanism of Injury
Most fractures of the distal phalanx are caused by crushing injuries, which result in one of several fracture patterns: comminuted (“crushed eggshell”), transverse, or longitudinal ( Fig. 3-1 ). Axial loads may also cause fractures of the distal phalanx. Frequently, distal phalanx fractures have associated extensive soft tissue injuries involving the tip of the finger, nail bed, or both. Avulsion fractures of the extensor and flexor tendons are discussed separately in the next section.
The patient usually reports a crushing injury to the distal phalanx. On examination, the distal phalanx is tender and swollen. Range of motion (ROM) may be limited by swelling and pain. It is crucial to ensure active flexion and extension of the DIP joint to document tendon integrity. The nail may be torn, and the nail bed may be lacerated. If the nail is intact, a subungual hematoma may be present. In some cases, substantial amounts of soft tissue may be avulsed from the tip of the finger or the palmar tuft over the distal phalanx. In all distal finger injuries, it is important to document sensation to two-point discrimination (the normal discrimination distance is 5 mm).
Three views of the distal phalanx are recommended: anteroposterior (AP), lateral, and oblique. Axial loads may cause either transverse or longitudinal fractures. The longitudinal fracture is usually stable, but the transverse fracture must be examined for angulation ( Fig. 3-2 ). The nail bed can sometimes become lodged within a transverse distal phalanx fracture. Widening of the fracture site on the lateral view and avulsion of the root of the nail plate may indicate this complication. Fractures of the distal tip (tuft fractures) are often comminuted.
Indications for Orthopedic Referral
Open fractures, intraarticular fractures, tendon compromise, and fractures with vascular compromise should be evaluated by a specialist within 2 to 3 hours of injury.
Angulated or displaced transverse fractures are often unstable and difficult to reduce because of interposition of soft tissue between the fracture fragments. If closed reduction is unsuccessful or reduction cannot be maintained with simple splinting, referral to an orthopedic surgeon for wire fixation is indicated.
Table 3-1 summarizes the management guidelines for distal phalanx fractures. The initial treatment of distal phalanx fractures should focus on management of the soft tissue injury and protective splinting. A U-shaped padded aluminum splint or fingertip guard should be anchored to the middle phalanx to provide protection for the tender distal phalanx and to maintain the DIP joint in extension. The splint should protect against blunt impacts to the fingertip during the healing period. Compressive circumferential taping of the distal phalanx should be avoided, especially in the case of a comminuted crush fracture. Elevation and ice should be used in the first 24 to 48 hours to reduce soft tissue swelling. The patient should be warned that these fractures may remain painful for months because of bleeding into the many fibrous septa in the finger pad.
|Splint type and position|
|Initial follow-up visit||1 to 2 weeks|
|follow – up care|
|Cast or splint type and position||Same as above|
|Length of immobilization||3 to 4 weeks or until finger is no longer sensitive to impact|
|Healing time||4 to 6 weeks|
|Comminuted fractures may take several months for complete resolution of symptoms|
|Follow-up visit interval||Every 2 to 4 weeks|
|Repeat radiography interval||Only need to repeat radiographs for persistent symptoms|
|Indications for orthopedic consult|
Nail Bed Injury
A large or painful subungual hematoma that is less than 48 hours old should be drained. Beyond this time frame, the hematoma may be too clotted for drainage. Decompression of the hematoma is most easily achieved by burning a hole in the nail with a hot paper clip or cautery unit. Two or three holes may be needed for adequate drainage. If the pressure of a handheld drill or 18-gauge needle is too painful, digital nerve block should be considered when a subungual hematoma is drained. A large hematoma (i.e., a subungual hematoma involving more than 50% of the nail) associated with a distal phalanx fracture usually indicates an underlying nail bed laceration. No clear advantage is gained from removing an intact nail to repair a nail bed laceration. The hematoma should be drained and the patient advised that there may be some deformity of the nail, although the intact nail usually lessens the deformity.
If the nail is avulsed, it should be removed and the nail bed repaired with absorbable interrupted sutures (6-0 or 7-0 chromic) under digital block anesthesia. The wound should be debrided of any nonviable or grossly contaminated tissue and thoroughly irrigated. The surrounding soft tissue injury should be loosely approximated. The cleansed nail should be placed back under the nail fold to splint the repair and to prevent adhesions from forming between the nail matrix and nail fold. Holes should be placed in the nail for drainage, and sutures should be placed laterally along the nail margins to prevent disruption of the germinal matrix of the nail. A sterile nonadherent dressing such as Vaseline gauze can be used as a substitute if the avulsed nail is unusable. The nail splint or gauze should remain in place for approximately 2 to 3 weeks until the new nail plate forms.
The use of prophylactic antibiotics after distal phalanx fractures complicated by nail bed laceration repair is controversial. A recent randomized controlled trial found no benefit with the addition of antibiotics to good wound care compared with placebo. A first-generation cephalosporin antibiotics for 5 to 7 days should be considered if gross contamination has occurred, if the wound is more than 24 hours old, or if the patient is immunocompromised.
Most fractures of the distal phalanx, including comminuted tuft fractures, heal well with protective splinting for 3 to 4 weeks. The DIP joint should be immobilized, leaving the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints free for ROM exercises. The splint should be used until the finger is no longer painful or sensitive to impact. Patients should be advised that some deformity of the nail is likely in the case of a nail bed injury, although the full extent of the deformity will not be apparent for 4 to 5 months.
Follow-up radiographs are not usually necessary because they do not alter management. However, repeat radiographs are recommended for evaluation of displaced transverse fractures that have undergone closed reduction or in patients who have severe symptoms despite splinting.
Return to Work or Sports
Patients with “crushed eggshell” or longitudinal fracture patterns may return to work or sports activities with adequate protection (e.g., “U”-shaped aluminum splint, volar splint) as long as pain is tolerable. Patients with transverse fractures should protect the finger until nontender because of the possible volar displacement of the distal fragment.
Delayed union can occur after a comminuted fracture of the distal phalanx. Nonunion is uncommon, but when present, it is usually caused by interposition of soft tissue between the fracture fragments. Patients with comminuted fractures may experience pain, hypersensitivity, or numbness and have difficulty with fine functions of the fingertip for several months.
Fractures of the distal phalanx in pediatric patients are usefully classified as extraphyseal or physeal. The management of extraphyseal fractures of the distal phalanx in children is similar to that in adults and is based on the stability of the fracture pattern and the status of the nail bed. Closed fractures with an intact nail bed are managed with splinting of the DIP joint and distal phalanx in extension for 3 to 4 weeks until clinical healing of the fracture site. The PIP joint should be left free for normal ROM. The patient may need protective splinting for contact activities for an additional 2 weeks. If the nail bed is lacerated, a digital nerve block is performed; the nail plate removed; and the nail bed debrided, irrigated, and repaired. Nail bed repair usually requires a fine absorbable suture material (e.g., 7-0 chromic). Unstable fractures (e.g., transverse fractures not reducible by closed means) should be referred to an orthopedic surgeon. Complications of distal phalanx fractures in pediatric patients include osteomyelitis and nail bed abnormalities. A patient with either of these complications should be referred to an orthopedic surgeon for definitive care.
Physeal injuries to the distal phalanx are discussed in the sections on mallet finger and jersey finger.
This is the most common closed tendon injury of the finger. Mallet finger occurs more often in men than in women, but affected women are approximately 10 years older than men with this injury. The long finger (third digit) is most commonly injured, followed by the ring finger, index finger, small finger, and thumb.
Mechanism of Injury
The so-called mallet finger injury is caused by avulsion of the extensor tendon from the dorsum of the base of the distal phalanx with or without an avulsed bony fragment. This injury results from forced flexion of the extended fingertip and can occur with sports (e.g., catching a ball) or with even minor household trauma (e.g., making a bed or dressing and undressing) ( Fig. 3-3 ).
A zone of relative avascularity exists in the extensor tendon 11 to 16 mm proximal to the insertion of the terminal tendon at the dorsum of the distal phalanx. This zone of relative avascularity predisposes the patient to injury at this site and contributes to the complications and delays in healing seen with the mallet finger injury.
The patient describes an injury consistent with forced flexion of the extended DIP joint and reports pain at the dorsum of the DIP. During physical examination, the patient has tenderness and swelling at the dorsum of the DIP and is unable to actively extend the DIP joint. Active extension at the DIP joint should be tested with all fingers in flexion. The typical mallet finger appearance is attributable to the unopposed flexor tendon at the DIP joint after the extensor tendon is avulsed ( Fig. 3-4 ). Varying degrees of loss of extension indicate whether the tear of the tendon is partial or complete. Patients with partial tears have weak active extension and a loss of 5 to 20 degrees of extension (“extensor lag”). With a complete tendon rupture, the patient has total loss of active extension, and a 50- to 60-degree deformity or extensor lag is typical. The size of the bony avulsion does not necessarily correlate with the amount of extensor function lost.
AP, lateral, and oblique views of the finger should be obtained. If radiographs show no apparent fracture, a pure tendon avulsion may have occurred. More commonly, a small fleck of bone may have been avulsed, which will be better visualized on the lateral view ( Fig. 3-5 ). Occasionally, as much as one third of the articular surface is avulsed, and volar subluxation of the distal fragment is seen.
Indications for Orthopedic Referral
Because surgical treatment may result in infection or an unacceptably stiff DIP joint and splinting the finger produces results similar to surgery for acute mallet finger injuries, surgical intervention is reserved for special cases or particular fracture patterns. Surgical referral should be considered for volar subluxation of the DIP joint ( Fig. 3-6 ), inability to fully extend DIP passively or a “swan-neck” deformity (i.e., hyperextension of PIP joint or flexion of DIP joint).
Surgical treatment decisions should be individualized and take into account the time since the injury, the degree of loss of extension, the amount of functional disability, the ability of the patient to comply with conservative treatment, and the potential economic hardship of prolonged splinting in certain occupations.
Table 3-2 summarizes the management guidelines for mallet finger fractures. Most patients with mallet finger injuries should be treated conservatively with prolonged splinting of the DIP joint in slight hyperextension. Success rates for conservative treatment are similar to those for surgical treatment, and patient satisfaction with the outcome of treatment is good. Successful closed treatment requires careful attention to the details of treatment to avoid complications and loss of position.
|Splint type and position||Dorsal padded aluminum splint, volar splint, stack splint |
DIP joint in slight hyperextension
|Initial follow-up visit||2 weeks|
|follow – up care|
|Cast or splint type and position||Same as above|
|Length of immobilization||6 to 8 weeks followed by 2 to 3 weeks of nighttime-only splinting|
|Healing time||8 to 10 weeks|
|Follow-up visit interval|
|Repeat radiography interval|
|Indications for orthopedic consult|
The DIP joint should be splinted in slight hyperextension without causing pain. This can be done with a dorsally-placed padded aluminum splint, a volar unpadded splint, or a Stack splint ( Fig. 3-7 ). The slightly hyperextended position of the DIP can be confirmed by inspection of the splinted finger from the lateral perspective. Overextension, which may lead to necrosis of skin over the DIP joint, should be avoided. Skin blanching while the splint is applied is a sign of overextension. It is important that the PIP joint is left free during splint application. Splinting has been shown to be effective for up to 3 months after injury. A Cochrane review did not find sufficient evidence that one type of splint was more effective than another.
Nonsurgical treatment of the majority of mallet finger injuries is safe, effective, well tolerated, and cost efficient. Mallet finger injuries should be splinted in slight hyperextension continuously for 6 to 8 weeks. The patient must not let the DIP joint drop into flexion at any time during the period of continuous splinting and should be instructed to support the tip of the finger at all times when changing the splint (e.g., after bathing). The patient usually needs some assistance in changing or reapplying the splint because two hands are needed to hold this alignment and properly apply the splint. Compliance with these instructions should be assessed at each follow-up visit at 2-week intervals until healing has occurred.
After the continuous splint has been discontinued, nighttime splinting is recommended for an additional 2 to 3 weeks. Alternatively, a weaning period can be initiated in which the splint is removed three times daily to allow ROM exercises for the DIP joint and then replaced. If flexion of the DIP joint occurs at some point during the healing process, the time clock goes back to “day 1,” and the 6-week splinting procedure should be restarted.
Complete radiographic healing of distal phalanx fractures often takes up to 5 months. Repeat radiographs should be obtained at the conclusion of continuous splinting and then every 1 to 2 months if the patient remains symptomatic.
Return to Work or Sports
Patients with mallet finger injuries may return to work or sports with adequate protection of the injury (i.e., splinting the DIP joint in slight hyperextension). After the period of mandatory splinting is completed (i.e., 6 to 10 weeks), further protective splinting or buddy taping may be needed for patients involved in occupations or sports that predispose them to reinjury for up to another 6 weeks.
Many patients initially have a slight to moderate extensor lag (i.e., lack of full extension of the DIP joint). After an appropriate trial of conservative therapy, some patients may continue to have a small extensor lag, especially if the patient sought treatment relatively late after injury. If the patient is not satisfied with some degree of extensor lag, another 6-week course of extension splinting may be performed with good results. However, only a minority of patients complain of difficulties with activities of daily living, and only a small percentage report work-related difficulties. Small degrees of extensor lag are a common complication of mallet finger injury but are surprisingly well accepted by most patients.
Late Mallet Finger
Although patients often seek treatment for the mallet deformity weeks or months after injury, many of these cases can be treated successfully up to 2 to 3 months after the initial injury. The patient should receive a trial of conservative therapy (i.e., splinting the DIP joint in slight hyperextension for 8 to 20 weeks). Patients must be warned about the poor prognosis for late-presenting mallet deformity because the longer the delay from injury to treatment, the less successful the result. Patients who have persistent symptoms after several weeks of splinting may benefit from operative repair. Left untreated, the mallet finger injury will progress to a swan-neck deformity of the finger (hyperextension of the PIP joint with flexion contracture of the DIP joint). A patient with this late sequela of an untreated mallet finger should be referred to an orthopedic surgeon.
In the pediatric age group, the mallet finger injury usually involves injury to the epiphysis at the base of the distal phalanx ( Fig. 3-8 ). Whereas children younger than 12 years of age are likely to sustain a Salter-Harris type I or II injury, teenagers are more likely to sustain a true bony mallet finger injury (i.e., a displaced type III fracture) ( Fig. 3-9 ). Follow-up care of nondisplaced pediatric mallet finger injuries requires splinting of the DIP joint in slight hyperextension for 4 to 6 weeks. It may be a challenge to get pediatric patients to adhere to continuous splinting. Casting or surgery should be considered if there is concern about adherence. Displaced fractures need to be reduced. Reduction requires digital nerve block with or without conscious sedation, gentle flexion of the distal phalanx to recreate the deformity, and extension of the distal fragment to restore bony congruity. The patient should be referred for surgical repair if closed reduction is unsuccessful or if the dorsal fragment is greater than 50% of the articular surface. Some clinicians recommend alternating between dorsal and volar splints to avoid skin breakdown dorsally or temporary paresthesias volarly. Radiographs are checked weekly for the first 2 weeks and then every 2 weeks until healing occurs to monitor the patient for signs of loss of reduction or volar subluxation of the distal fragment. A variant of Salter-Harris types I and II fractures is a Seymour fracture, which includes avulsion of the proximal edge of the nail from the eponychial fold. This is considered an open fracture and should be treated as such. Management includes debridement, nail removal, irrigation, reduction as needed, nail replacement, and antibiotics. Failure to recognize these fractures may result in substantial complications.
As in adult patients, extensor lag is a common complication in pediatric mallet finger injuries. Extension splinting can be continued but is less effective after the third or fourth month. However, extensor lag of up to 10 degrees is well tolerated by most patients.
Flexor Digitorum Profundus Avulsion (Jersey Finger)
The ring finger is most commonly injured (75% of FDP injuries) because of its exposed and vulnerable position when the fingers are flexed. Three types of FDP avulsion injury have been described ( Fig. 3-10 ).
In a type I injury, the tendon is retracted to the palm so that both vincula are ruptured with some loss of blood supply. The palm is tender at the lumbrical level. Radiographs show no fractures. Patients with this type of injury should be referred immediately because surgery must be undertaken within 7 to 10 days or tendon retraction, and scarring will be irreversible.
The most common type of FDP avulsion is the type II injury in which the tendon is avulsed and retracted to the level of the PIP joint. In this injury, the long vinculum remains intact, so some blood supply is retained. Radiographs often show a small fleck of bone at the level of the PIP joint, which is best seen on the lateral view. The volar aspect of the PIP is tender and swollen, and the patient is unable to actively flex the DIP joint. Because the length of the tendon is largely preserved and some blood supply is maintained, the tendon can often be reinserted 2 to 3 months after injury. It is important to be aware that a type II injury can become a type I injury if the remaining vinculum gives way and the tendon is then retracted into the palm.
In a type III injury, a large bony fragment is avulsed from the volar aspect of the distal phalanx, which causes the tendon to be held at the level of the A-4 pulley. In this injury, both vincula are intact, and blood supply to the tendon is preserved. Open reduction and internal fixation of the large bony fragment are required but can be performed as late as 2 to 3 months after injury.
Mechanism of Injury
The so-called jersey finger injury is caused by avulsion of the FDP tendon from the volar base of the distal phalanx and usually occurs as a player grabs another’s jersey. The avulsion is caused by forced extension while the DIP joint is held in flexion.
Avulsion of the FDP is an uncommon injury and is often missed on initial presentation or may go unnoticed for a number of weeks. The diagnosis is based on the typical mechanism of injury along with an inability to actively flex the DIP joint. FDP integrity is tested by stabilizing the PIP in extension by holding the middle phalanx and asking the patient to flex at the DIP joint. An inability to flex the DIP is consistent with FDP injury. The site of maximal tenderness may give a clue as to how far the tendon is retracted, but this is not always accurate.
Lateral and oblique views are needed to identify an avulsed fragment of bone associated with an FDP avulsion. Good-quality radiographs and often a “hot light” are required to identify a small avulsed fleck of bone. The level at which the bony fragment is seen is quite variable, but it often becomes trapped near the middle phalanx and PIP joint.
Prompt diagnosis and early referral are vital to treatment of patients with this injury. This injury is not amenable to outpatient management. The injured finger should be splinted with the DIP and PIP joints in slight flexion while the patient awaits referral to an orthopedic or hand surgeon. The timing of surgery can vary: for patients with type I injuries, immediate surgery is recommended; surgery may be deferred for several days to weeks for patients with type II or type III injuries.
Return to Work or Sports
The repaired tendon must be protected from disruptive forces for 6 to 12 weeks—approximately 12 weeks for type I injuries and 6 to 8 weeks for type II or III injuries. Early rehabilitation is important to obtain the best clinical result.
If the FDP is avulsed and retracted to the level of the palm (i.e., a type I injury), the tendon’s blood supply may be interrupted, and bleeding into the tendon sheath may lead to fibrosis and scarring. Flexion deformities of the injured finger may result. Patients with type I injuries who seek treatment weeks to months after injury have a poor prognosis and may require arthrodesis, tenodesis, or a free tendon graft. The outcome of late surgical intervention for patients with type I injuries is poor, and no further treatment may be an appropriate choice for some patients. Surgically repaired FDP may lose some DIP extension; however, grip strength and DIP joint flexion are generally preserved.
Avulsion of the FDP is seldom seen in school-age children but does occur in adolescents. Unlike the common pattern in the adult, a fragment of the metaphysis and a variable amount of the physis is avulsed (Salter-Harris type IV) in adolescent patients. This fragment is tethered at the distal edge of the A-4 pulley (similar to the type III injury in adults). In this type of injury, the length of the tendon and its blood supply are preserved. The patient’s DIP and PIP joints should be splinted in slight flexion and the patient referred promptly to a hand surgeon. Heavy sutures, mini-screws, and pullout wires have all been successful in bone-to-bone fixation. Pinning of the joint should be avoided to allow early ROM exercises for the DIP joint.
Distal Interphalangeal Joint Dislocation
Pure dislocations and fracture dislocations of the DIP are uncommon injuries. They are nearly always dorsal and may be associated with open wounds. The most common mechanism of injury is hyperextension of the DIP joint. Fracture dislocations of the DIP joint nearly always involve avulsions of the extensor or flexor tendons, as discussed earlier.
Patients with a dorsal dislocation of the DIP joint have an obvious deformity of the fingertip. The dislocation is often reduced by the patient or someone else before seeking medical care. A lateral radiograph easily identifies this injury ( Fig. 3-11 ).
Simple longitudinal traction under digital block anesthesia is usually all that is required to reduce the dislocation. Occasionally, hyperextension followed by traction and digital pressure is necessary. If the reduction is maintained with active ROM, the joint is considered stable. The DIP joint should be splinted in extension for 2 to 3 weeks. Open reduction is necessary for any dislocation that is irreducible.
Middle Phalanx Shaft Fractures (Adult)
At the volar aspect of the PIP joint, the flexor digitorum superficialis (FDS) splits to allow the profundus tendon to pass between its two slips. The FDS inserts broadly along the volar surface of the middle phalanx. Thus, a fracture at the neck of the middle phalanx results in apex volar angulation as the proximal fracture fragment is pulled into flexion by the FDS ( Fig. 3-12, A ). A fracture at the base of the middle phalanx results in apex dorsal angulation as the distal fragment is pulled into flexion by the FDS ( Fig. 3-12, B ). Fractures through the middle two thirds of the shaft of the middle phalanx may be angulated in either direction.